City became the first side in a decade to retain the Premier League title last weekend, holding off Liverpool by a single point at the end of a thrilling race thanks to a run of 14 consecutive league wins to end the season.

Manchester City are on the brink of a domestic treble, with only Watford standing in their way in Saturday’s FA Cup final, but a potentially historic season risks being overshadowed by several probes into the club’s off-field conduct.

City became the first side in a decade to retain the Premier League title last weekend, holding off Liverpool by a single point at the end of a thrilling race thanks to a run of 14 consecutive league wins to end the season.

Pep Guardiola’s men also retained the League Cup in February, the first leg of their potential domestic clean sweep, which has never before been done in England.

However, the club have spent much of the week preceding the Wembley showcase responding to reports that they could be set for a season’s ban from the Champions League over alleged breaches of financial fair play rules.

The case was referred to UEFA’s adjudicatory chamber on Thursday to decide what sanction, if any, should be imposed. City replied, saying they were “disappointed, but regrettably not surprised” by the move from European football’s governing body.

Reports by German publication Der Spiegel had alleged that City, bankrolled by Sheikh Mansour, a member of Abu Dhabi’s royal family, set up sponsorship deals to circumvent regulations limiting how much money owners can put into a club.

However, that is not the only current investigation into City’s practices off the field.

England’s Football Association said in February it was investigating allegations that City paid £200,000 ($256,000) to Borussia Dortmund winger and England international Jadon Sancho’s agent when the player was 14.

FA rules state that young players cannot be represented by an agent until the year they turn 16.

And the English champions could be hit with a two-window transfer ban by FIFA over the recruitment of foreign minors and alleged breaches of third-party ownership.

“I’m not too much concerned or worried about what people say,” City boss Guardiola previously insisted when questioned whether the investigations threaten to taint his legacy at the club.

“If we have made mistakes we will be punished -- it is what it is, on and off the pitch -- but I’m pretty sure what we have done is incredible.”

- Record-breakers -

Guardiola’s side have smashed a host of records during his three-year spell in charge, despite a disappointing trophyless debut campaign in England.

However, a first-ever clean sweep of League Cup, Premier League and FA Cup would give this City side a claim to be the best England has ever produced.

“I’m desperate, desperate, desperate to win the FA Cup. You don’t even know how much it’s a priority,” said City captain Vincent Kompany after lifting the Premier League last weekend.

Kompany could make his final City appearance at Wembley with the Belgian’s contract up in the summer and no new deal agreed as yet.

City won their fifth FA Cup in 2011, the first silverware since Sheikh Mansour’s takeover, but will be wary of complacency after slipping up against Wigan at Wembley in 2013.

In contrast to City’s trophy-laden decade, Watford have never won a major trophy.

And despite losing twice to Guardiola’s men in the league this season, Hornets boss Javi Gracia, whose side mounted an impressive comeback to beat Wolves in the semi-final, is taking heart from both games.

“I think it showed us it’s possible,” said the Spaniard. “We lost both games but I think we showed that we can beat them.

“We competed really well in both games in different moments. In the first game we lost 2-1 but we competed until the end and had chances at the end. In the second one we kept the result until the second half and then they scored from an offside position and the game changed.”